Development environments provide a sandbox where you can work on your application without affecting the live site.
Back up Your Drupal Site
TopicA reliable backup will allow you to restore your site if something goes wrong.
PhpStorm
TopicThe PhpStorm integrated development environment (IDE) contains dozens of useful features that make working with a Drupal codebase easier.
JavaScript in Drupal
TopicJavaScript files are included by a module or a theme by creating an asset library. Using this asset library system you can selectively choose which files to load, overwrite existing files, or customize them to suit your needs.
Drush
TopicDrush is a command line interface that enables you to interact with your Drupal site without clicking around the graphical user interface (GUI).
Forms (Form API)
TopicDrupal provides a standard, secured method for module developers to add forms to a Drupal website. Learn how to use the Form API to build, validate, and submit a custom form.